A three-dimensional display device, in which a parallax barrier layer is provided for an LCD panel so as to face the viewer, is known in the art. For example, Japanese Patent Application Laid-Open Publication No. 11-95167 discloses a three-dimensional display device 200 as schematically shown in FIG. 4.
The three-dimensional display device 200 shown in FIG. 4 includes an LCD panel 52 as a display panel and a substrate 53 with a parallax barrier layer (which will be referred to herein as a “parallax barrier substrate 53”), which is provided in contact with the surface of the LCD panel 52 so as to function as optical splitting means for splitting incoming light into right and left pictures. The parallax barrier substrate 53 is obtained by providing a parallax barrier layer 82, consisting of a lot of striped opaque portions, on a substrate 81 made of glass or a transparent resin, for example. The parallax barrier substrate 53 is arranged such that the surface of the substrate 81 thereof contacts with the surface of the LCD panel 52.
In the LCD panel 52, a liquid crystal layer 73 is sandwiched between two glass substrates 72 and 74, a light-outgoing-side polarizer 71 is provided on the glass substrate 72 that is located closer to the viewer (such a location will be referred to herein as “on the light outgoing side”), and a light-incoming-side polarizer 75 is provided on the glass substrate 74 that is located closer to a backlight 51 (such a location will be referred to herein as “on the light incoming side”). In the liquid crystal layer 73 of the LCD panel 52, right-eye and left-eye pictures are alternately arranged every other column. The right-eye picture, obtained by transmitting the light coming from the backlight 51, is split by the parallax barrier substrate 53. As a result, the viewer sees only the left-eye picture with his or her left eye and only the right-eye picture with his or her right eye, thereby sensing a three-dimensional picture.
In this three-dimensional display device 200, the surface of the polarizer 71 of the LCD panel 52 is covered with an antireflection coating 76 to minimize the reflection at the interface where the parallax barrier substrate 53 and the LCD panel 52 contact with each other. As a result, the amount of light reflected back from the interface through the LCD panel 52 can be reduced and therefore, interference fringes, which would otherwise be produced a lot due to an interference with the light reflected by the polarizer 71, can be cut down.
In every conventional three-dimensional display device including this three-dimensional display device 200 (see FIGS. 4 through 7 of the publication identified above), the parallax barrier substrate 53 is bonded as an external member to the LCD panel 52 including the polarizer 71. That is to say, between the parallax barrier layer 82 and pixels (i.e., the liquid crystal layer 73), the viewer-side substrate 72 of the display panel, the polarizer 71, the antireflection coating 76 and the substrate 81 are stacked in this order as viewed upward from the liquid crystal layer 73. In addition, an adhesive layer (not shown) for bonding the parallax barrier substrate 81 is further provided.
For that reason, it is difficult to accurately control the distance between the parallax barrier layer 82 and the pixels or to make this distance uniform all over the display plane. Furthermore, it is also hard to position the parallax barrier layer 82 with respect to the pixels on the display plane with sufficiently high accuracy.
If the distance from the parallax barrier layer 82 to one pixel (of the liquid crystal layer 73) were different from the distance from that layer 82 to another pixel within the same plane, then interference fringes or moire fringes would be created or the display luminance might vary, thus possibly deteriorating the display quality.
Also, if the positioning accuracy were low within the display plane, then the pixel aperture ratio might decrease so much as to create moire fringes, too.
Furthermore, as there are a lot of interfaces between the liquid crystal layer 73 and the viewer, the display quality might be decreased seriously by a significant loss of the light due to reflection at those interfaces.
The higher the definition of display panels, the more critical these various problems are likely to get. Furthermore, particularly in a method of fabricating a display device in which a large scale panel is fabricated by performing a single flow of processing steps on the same big substrate and then divided into a number of smaller scale panels, if the parallax barrier substrate were bonded to the large scale panel, then those problems would arise easily to decrease the yield and productivity significantly. What is worse, once the parallax barrier substrate has been bonded, it is very difficult to cut the assembly into smaller pieces just as intended.